Improvement in saw-mills



PATENT OFFICE. N

ALBERT M. DEXTER, 0F MATTAPOISETT, MASSACHUSETTS.

IMPROVEMENT IN SAW-MILLS.

Specification forming part of Letters Patent N o. 116,569, dated July 4, 1871.

` To all whom t may concern:

Be it known that I, ALBERT M. DEXTER, of Mattapoisett, in the count-y of Plymouth and State of Massachusetts, have invented certain Improvements in Box-Board Machines, of which the following' is a specification:

The first part of my invention relates to the manner of setting the log toward the saw so as to saw various thicknesses; and the second part relates to the ina-nner of running the carriage forward and backwa-rd, the whole being entirely selfoperating when set running with the log in place.

Fi gnre I is a plan of the carriage, showing the log in place. Fig. II is a side elevation, showing the log in place, the carriage, set-works, and shipper-bar. Fig. III is a plan of the frame, showing the seve 1al devices which carry the carriage forward and backward. Fig. IV is a vertical transverse section, showing the carriage in its working position with the log in place.

H is the head-stock, to which the log L is secured by the dogs dd. S S are the screws by means of which the setting is accomplished, and, as they are connected by the chain x and sprocket-wheels 11, turn simultaneously.` S Wis the set-wheel, which meshes into the rack 3 on setrod V, making only a part of a revolution, and is provided with a pawl, which acts on the side teeth of the sIn'ocket-wheel l (Fig. IV) in such a manner as to allow the set-rod V to be drawn back till the screw at p strikes the slide E, and, on being driven into the position now seen, will carry the screws S S such a part of a revolution as to set the log Il enough for the required board. Now, as the thickness of the boards to be sawn is determined by the distance which the set-rod V may be drawn back, I have provided the machine with the bar O, on which the slide E may be fixed and held by the pin a, which passes through the slide and one of the several holes in the bar O. Now, by means ofthe bar O, the slide E, the pin u, and the screw p, I am enabled to control the exact distance which the set-rod V may be drawn back, and hence the thickness of boards to be sawn within the limits of the machine, which is generally one-eighth to one inch in thickness. Now7 as the carriage advances, and just as the board is sawn from the log, the stop r. strikes the horn B,on shipper-bar S B, and the set-rod V is drawn back till the screw p strikes the slide E, which distance then gives a certain thickness of board, and at this point the shipperbar S B is carried forward till a change is made in the feed-works, when the carriage runs back, the set-rod V is driven in by striking the buttblock at t, and the horn on the carria-ge at A draws the shipper-bar S B back, (as seen in Fig. II,) when the carriage advances again as before. Now t-o enable others skilled to understand the manner in which the carriage (Figs. I and II) is carried forward and backward, I refer to Figs. III and IV. On the feed-shaft It is a pinion, T, which meshes into the rack on the carriage, seen at T in Fig. IV. i

Motion is given to the operating part-s in the usual way, except to the loose pulley k, which is made to-tnrn in the direction ofthe arrow by means of a cross-belt, not seen in the drawing. When the clutch D is in the position seen in Fig. III the pulley h carries the shaft R and pinion T forward; and when the clutch D is shifted over close to loose pulley M, the order of motion is reversed and the carriage runs backward. The shifting of the clutch D from loose pulley 7a to loose pulley M andback, is accomplished as follows:A Fastened to the bar b is a roll, which plays in the diagonal slot c as the bar b moves forward and backward. By means of the shipper-bar S B the bar b is carried forward, as before shown, and by the action of the roll in slot c the lever Lis carried over toward the spring F', thus compressing the spring; and at this point the latch h is let off by the end of the mortise in shipper-bar, (seen at h /L in Fi e'. II,) and the spring shifts the clutch D over so as to lock it into loose pulley M, when the latch h springs on and holds the clutch D in that position till the carriage runs back and the horn or carriage at A, Fig. II, carries the shipper-bar S B backward and lets off the 4latch lz., when the the spring F will shift the clutch D back to its position now seen, and so on till you wish to stop the carriage, when it is only necessary to move the bar y back till the lever I strikes into the notched end *and holds the clutch l) midway between the loose pulleys It' and M.

Thus, with this'ar 1angement and combination of old devices, I am able to produce the most complete box-board machine ever known. I

heve11ot described the more (50111111011 parts ot' such machines, as those skilled may see dit once their nature and use. s

I do 11ot claim the several devices separately, as they have been lo11 g i11 use; but

What I (lo claim as 111y invention, zuid desire to secure by Letters Patent, is-

1. The slide E and pin u., i11 Combination with with the bar 0 and screw p, as and for the 11111'- pose hereinbefore set forth.

L. The springs F IT mld latches .h h', iu eo111bination with the levers I and 4, substantially as and for the purpose herein speeiied.

VVituesses: ALBERT M. DEXTER.

E. L. DEXTER, G. H. DEXTER. 

